You're right, it's probably not important, just darned weird.
I think it’s just a poor image with bad lighting, but he’s not the focal point anyway, beard or not, does it matter?
Wearing what appears to be a hospital orderly outfit is interesting however...if that photograph was taken in Kenya...it was when he was supposedly working for SHELL in Nairobi.
The photo of 0bama Sr (or whatever..) and Ruth and two boys looks sort of shortened, maybe the photo was slightly curved when it was photographed again or however it was reproduced. Obama’s torso is too short. His clothes do sort of look like a hospital suit but I think in a clearer photo might be another sort of uniform or clothing.
You're right, it's probably not important, just darned weird.